Ceramic materials prepared from various metal oxides have been used in diverse applications. These ceramic materials can be prepared by first forming a green body that contains metal oxide particles. The green body is subsequently sintered to consolidate the particles into a dense body and to achieve the desired final properties.
Many ceramic materials are aluminum-based or silicon-based. Some zirconia-based ceramics have also been prepared. Compared to other ceramic materials, zirconia-based ceramics can have improved mechanical strength associated with a phase transformation mechanism that can be triggered when a crack propagates into the ceramic material. More specifically, tetragonal phase zirconia can be transformed to monoclinic phase zirconia under such conditions. The formation of the monoclinic phase tends to arrest the progression of the crack throughout the ceramic material.